Re: [PATCH v9 3/4] phy: Add Sparx5 ethernet serdes PHY driver

From: Andrew Lunn
Date: Wed Dec 09 2020 - 21:12:50 EST


> diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
> index 01b53f86004c..f6a094c81e86 100644
> --- a/drivers/phy/Kconfig
> +++ b/drivers/phy/Kconfig
> @@ -66,9 +66,11 @@ source "drivers/phy/broadcom/Kconfig"
> source "drivers/phy/cadence/Kconfig"
> source "drivers/phy/freescale/Kconfig"
> source "drivers/phy/hisilicon/Kconfig"
> +source "drivers/phy/intel/Kconfig"

That looks odd.

> source "drivers/phy/lantiq/Kconfig"
> source "drivers/phy/marvell/Kconfig"
> source "drivers/phy/mediatek/Kconfig"
> +source "drivers/phy/microchip/Kconfig"
> source "drivers/phy/motorola/Kconfig"
> source "drivers/phy/mscc/Kconfig"
> source "drivers/phy/qualcomm/Kconfig"
> @@ -80,7 +82,6 @@ source "drivers/phy/socionext/Kconfig"
> source "drivers/phy/st/Kconfig"
> source "drivers/phy/tegra/Kconfig"
> source "drivers/phy/ti/Kconfig"
> -source "drivers/phy/intel/Kconfig"
> source "drivers/phy/xilinx/Kconfig"

Ah. Please make that a separate patch.

> + value = sdx5_rd(priv, SD25G_LANE_CMU_C0(sd_index));
> + value = SD25G_LANE_CMU_C0_PLL_LOL_UDL_GET(value);
> +
> + if (value) {
> + dev_err(macro->priv->dev, "CMU_C0 pll_lol_udl: 0x%x\n", value);
> + ret = -EINVAL;
> + }
> +
> + value = sdx5_rd(priv, SD_LANE_25G_SD_LANE_STAT(sd_index));
> + value = SD_LANE_25G_SD_LANE_STAT_PMA_RST_DONE_GET(value);
> +
> + if (value != 0x1) {
> + dev_err(macro->priv->dev, "sd_lane_stat pma_rst_done: 0x%x\n", value);
> + ret = -EINVAL;
> + }

These error messages are not very helpful. Could you be a bit more
descriptive. Or do you think there is sufficient black magic in the
hardware that nobody outside of Microchip will be able to debug it?

> +static int sparx5_serdes_get_serdesmode(phy_interface_t portmode,
> + struct phy_configure_opts_eth_serdes *conf)
> +{
> + switch (portmode) {
> + case PHY_INTERFACE_MODE_1000BASEX:
> + if (conf->speed == SPEED_2500)
> + return SPX5_SD_MODE_2G5;
> + if (conf->speed == SPEED_100)
> + return SPX5_SD_MODE_100FX;
> + return SPX5_SD_MODE_1000BASEX;

Please could you explain this. Why different speeds for 1000BaseX?

> + case PHY_INTERFACE_MODE_SGMII:
> + return SPX5_SD_MODE_1000BASEX;

Here there could be some oddities, depending on how 10Mbps and 100Mbps
is implemented. But 1000BASEX only supports 1Gbps.

> +static int sparx5_serdes_validate(struct phy *phy, enum phy_mode mode,
> + int submode,
> + union phy_configure_opts *opts)
> +{
> + struct sparx5_serdes_macro *macro = phy_get_drvdata(phy);
> + struct sparx5_serdes_private *priv = macro->priv;
> + u32 value, analog_sd;
> +
> + if (mode != PHY_MODE_ETHERNET)
> + return -EINVAL;
> +
> + switch (submode) {
> + case PHY_INTERFACE_MODE_1000BASEX:
> + case PHY_INTERFACE_MODE_SGMII:
> + case PHY_INTERFACE_MODE_QSGMII:
> + case PHY_INTERFACE_MODE_10GBASER:
> + break;
> + default:
> + return -EINVAL;
> + }
> + if (macro->serdestype == SPX5_SDT_6G) {
> + value = sdx5_rd(priv, SD6G_LANE_LANE_DF(macro->stpidx));
> + analog_sd = SD6G_LANE_LANE_DF_PMA2PCS_RXEI_FILTERED_GET(value);
> + } else if (macro->serdestype == SPX5_SDT_10G) {
> + value = sdx5_rd(priv, SD10G_LANE_LANE_DF(macro->stpidx));
> + analog_sd = SD10G_LANE_LANE_DF_PMA2PCS_RXEI_FILTERED_GET(value);
> + } else {
> + value = sdx5_rd(priv, SD25G_LANE_LANE_DE(macro->stpidx));
> + analog_sd = SD25G_LANE_LANE_DE_LN_PMA_RXEI_GET(value);
> + }
> + /* Link up is when analog_sd == 0 */
> + return analog_sd;

The documentation says:

/**
* @validate:
*
* Optional.
*
* Used to check that the current set of parameters can be
* handled by the phy. Implementations are free to tune the
* parameters passed as arguments if needed by some
* implementation detail or constraints. It must not change
* any actual configuration of the PHY, so calling it as many
* times as deemed fit by the consumer must have no side
* effect.
*
* Returns: 0 if the configuration can be applied, an negative
* error code otherwise
*/

So why are returning link up information?

Andrew